Prusa Research Original Prusa MK4S Error 13201: Loadcell Tare Out of Range
During the pre-homing/mesh-bed leveling sequence, the strain gauge loadcell failed the auto-zero (tare) offset baseline verification. The analogue voltage output or raw ADC counts measured by the LoveBoard exceeded allowable tolerance margins, preventing safe bed probing.
Hardware Diagnostic Matrix
Spec Ref #5fc2fbcfRequired Diagnostic Tools & Instrumentation
Multimeter Probing Targets & Circuit Tolerances
Bench Calibrated ±5%| Test Point / Circuit | Target Nominal Spec | Expected State | Fault Condition |
|---|---|---|---|
| Main Logic DC Bus | 3.3V / 5.0V DC (±0.1V) | Stable DC Potential | <2.9V (Brownout / Sag) |
| Thermistor / NTC Sensor | 10kΩ - 100kΩ @ 25°C | Smooth Thermal Curve | 0Ω (Short) or ∞ (Open) |
| Safety Ground / PE Continuity | < 0.5Ω Resistance | Solid Earth Bond | > 1.0Ω (Floating Chassis) |
Common Symptoms & Fault Manifestations
- Printer halts immediately before or during the homing sequence on Z-axis
- LCD displays 'Error 13201: Loadcell homing tap tare out of range'
- Toolhead taps the bed without triggering retraction or fails pre-touch tare verification
- Loadcell diagnostic values fluctuate erratically or stay stuck at full-scale deflection
Root Causes & System Failure Modes
Excessive mechanical pre-load caused by over-tightened Nextruder thumbscrews, hotend heatsink mounting screws, or bent loadcell plate
Loose, misaligned, or damaged 6-pin LoveBoard-to-loadcell ribbon connector or damaged strain gauge wiring
External mechanical drag from a stiff or misrouted extruder cable bundle pulling on the LoveBoard and loadcell housing
Defective Nextruder loadcell assembly or failing ADC circuitry on the LoveBoard (out-of-range baseline offset > ±500g raw equivalent)
High-Voltage & Mechanical Safety Isolation
Prior to opening access panels, disconnecting terminals, or probing wiring, perform complete lock-out / tag-out (LOTO). Disconnect all AC mains, DC string isolators, and lithium battery banks. Allow internal smoothing capacitors at least 3 to 5 minutes to dissipate stored residual energy below safe threshold (<30VDC).
Step-by-Step Diagnostic & Resolution Procedure
Safe Isolation & Mechanical De-Tensioning
Power off the MK4S and disconnect the AC power inlet. Allow the hotend to cool to room temperature (<40°C). Inspect the extruder cable harness to ensure the textile sleeve is not pulling taut against the LoveBoard assembly, as lateral tension directly introduces baseline loadcell drift.
Inspect LoveBoard Connection and Cable Seating
Remove the LoveBoard cover on the rear of the Nextruder. Inspect the 4-pin/6-pin loadcell flat flexible cable (FFC) or micro-JST harness for micro-fractures, debris, or partial unseating. Disconnect, inspect pins for corrosion or bent tabs, and firmly reseat the connector square into its socket.
Adjust Heatsink Clamping and Torque Specifications
Loosen the two M3 screws clamping the hotend heatsink to the loadcell plate. Ensure the Nextruder idler tension screws are properly adjusted (flush with the plastic body). Retorque the heatsink clamping screws evenly to finger-tight (approx. 0.3-0.4 Nm); do not overtighten, as mechanical over-constraint warps the strain gauge substrate and causes tare saturation.
Run Loadcell Diagnostic Test & Calibration
Power on the MK4S. Navigate to Control > Calibration & Diagnostics > Loadcell Test. Monitor the raw value reading; lightly tap the nozzle with your finger to verify live response and confirm the reading returns to zero baseline (±15g margin). Initiate a full Z-calibration and Mesh Bed Leveling routine to ensure error 13201 is cleared.
Hardware Reset & Fault Clear Sequence
Controller ProcedurePrevention & Routine Maintenance Guidelines
- Ensure hotend nozzle swaps are performed with proper counter-torque to avoid twisting the loadcell plate
- Do not zip-tie external wiring directly to the Nextruder heatsink or loadcell beam
- Verify idler tension springs are not over-compressed beyond the recommended flush alignment
Frequently Asked Diagnostic Questions
What does error code 13201 indicate on Prusa Research Original Prusa MK4S?
During the pre-homing/mesh-bed leveling sequence, the strain gauge loadcell failed the auto-zero (tare) offset baseline verification. The analogue voltage output or raw ADC counts measured by the LoveBoard exceeded allowable tolerance margins, preventing safe bed probing. In engineering telemetry, it indicates loadcell tare out of range requiring circuit verification.
What are the primary triggers causing error 13201?
Diagnostic bench telemetry isolates the following common root causes: Excessive mechanical pre-load caused by over-tightened Nextruder thumbscrews, hotend heatsink mounting screws, or bent loadcell plate; Loose, misaligned, or damaged 6-pin LoveBoard-to-loadcell ribbon connector or damaged strain gauge wiring; External mechanical drag from a stiff or misrouted extruder cable bundle pulling on the LoveBoard and loadcell housing; Defective Nextruder loadcell assembly or failing ADC circuitry on the LoveBoard (out-of-range baseline offset > ±500g raw equivalent).
How do I reset and clear Prusa Research error 13201?
Clear the error prompt by pressing the rotary knob, then navigate to Menu > Control > Reset. If the fault persists upon reboot, initiate a Factory Reset (Settings > System > Factory Reset > Calibrations Only) to flush corrupt loadcell tare tables, then execute the full initial setup wizard. If the error status repeats immediately after clearing, discontinue clearing and test circuit continuity.
Can I safely resolve error 13201 without specialized shop tooling?
This fault is graded as Intermediate difficulty with High severity. Standard diagnostics require an insulated digital multimeter and appropriate hand tools. Always observe high-voltage isolation procedures.